1. Field of the Invention
The present invention relates to a pipeline lining method, and more specifically relates to a pipeline lining method for lining a pipeline in order to repair an aged pipeline.
2. Description of the Prior Art
In order to repair an aged sewer pipe or other pipeline buried under ground without removing it therefrom, pipeline lining methods have been proposed in which a tubular pipe lining material impregnated with a thermosetting resin is inserted into the pipeline, the pipe lining material is expanded by air pressure or the like and pressed against an inner peripheral surface of the pipeline, and the thermosetting resin impregnated in the pipe lining material is heated and cured to line the pipeline. To heat and cure the pipe lining material, a method is employed in which steam (water vapor) or a hot water shower is used. A heating method is also proposed in which hot water is sprayed or made into a mist, or in which the pipe is filled with hot water.
A method is also known from, e.g., Japanese Patent No. 2501048 in which curing is achieved by a hot water shower. In such a method, a hot water hose in which a plurality of spray openings for spraying hot water is formed at predetermined intervals in a length direction is inserted into the pipeline along with the pipe lining material, and the pipe lining material is expanded by air pressure. High-temperature hot water is then pressurized and supplied to the hot water hose while the pipe lining material is pressed against the inner peripheral surface of the pipe. Hot water is sprayed as a hot water shower from the spray openings of the hot water hose and is blown against the inner peripheral surface of the pipe lining material to heat and cure the pipe lining material.
Since the pipe lining material is still hot after the pipe lining material has been cured, cool water (normal temperature) is prepared by a separate water-supplying truck, and the cool water is sprayed onto the pipe lining material to cool the hot pipe lining material.
However, in the prior art, a water truck for supplying cool water must be provided separately from the device for supplying the hot water used to thermally cure the pipe lining material in order to cool the cured pipe lining material. A problem therefore arises in that the water truck must be transported and a parking space must be made available for the water truck.
Other difficulties have been encountered in the conventional methods for curing the lining material. With methods for filling the pipe with hot water, a large amount of water is required. With methods in which the hot water is sprayed in a punctual pattern, the temperature of the entire lining material is not readily controlled. Therefore, some parts of the lining material will become hot before other parts, curing will be inconsistent, and a stable quality will not be readily guaranteed.
Furthermore, dramatic variations occur due to pressure and hole size when hot water is sprayed, and uniform spraying is not readily achieved.
Therefore, it is an object of the invention to provide an inexpensive pipeline lining method that enables the pipe lining material to be uniformly heated and cured and the thermally cured pipeline lining material to be cooled at a low cost.